Scientists confirm link between drinking very hot beverages and oesophageal cancer
A large-scale British study has found that regularly drinking very hot tea or coffee raises the risk of oesophageal cancer. Researchers advise letting drinks cool before consuming them.
British scientists have conducted what is so far the largest study on the topic, surveying nearly a million people, and concluded that drinking very hot beverages such as tea or coffee may increase the risk of oesophageal cancer. The findings were reported by the BBC Russian Service.
According to the data, participants who drank "very hot" beverages had roughly three times the cancer risk of those who drank warm tea or coffee. The researchers believe hot liquid may damage cells in the lining of the oesophagus.
The Oxford University study, published in the International Journal of Cancer, defines any drink at 65 degrees Celsius or higher as "very hot" and potentially risky. Drinking six or more hot beverages a day also raises the risk. Adding milk cools a drink somewhat, but researchers say the temperature can still remain high enough to pose a risk with regular consumption.
Tea brewed immediately after water boils can reach around 100 degrees Celsius; once poured into a cup, it typically drops to about 90–95 degrees. Scientists recommend waiting a few more minutes before drinking tea or coffee so it cools to a safer temperature. Cancer Research UK says it is hard to specify exactly how long to wait, advising instead simply to wait until a drink is comfortable to drink rather than consuming it while still very hot.
One of the study's authors, Keren Papier, noted that research in South America, where many people drink very hot mate, has already shown a similar link between hot beverages and oesophageal cancer. However, she added that further research is needed to pinpoint the exact temperature associated with increased risk.
A separate study involving 118 young people tasting various coffees found that most considered drinks too hot only starting at 70 degrees Celsius. MTPak Coffee, a maker of paper cups for hot drinks, says the ideal temperature for takeaway coffee is 49–60 degrees, though baristas may serve it above 82 degrees if a customer requests it very hot.
Other cancer risk factors
According to Worldwide Cancer Research, oesophageal cancer is the tenth most common cancer worldwide and the seventh most common cause of cancer death. Symptoms are minimal or absent in early stages, so diagnosis often comes late. Symptoms include difficulty swallowing, heartburn or acid reflux, nausea or vomiting, hoarseness, and loss of appetite.
Researchers estimate that one or two in ten oesophageal cancer cases could be prevented if people stopped drinking very hot beverages. Squamous cell oesophageal cancer is rare, and in the UK about 1% of the population has a lifetime risk of developing it. Other factors, particularly smoking, have a far greater effect on overall risk. Fiona Osgun of Cancer Research UK stressed that the most important ways to reduce the risk of this cancer are not smoking and cutting down on alcohol consumption.
